Hot knife and method of use



Oct. 13, 1936. J. R, GAMMETER 2,057,021

HOT KNIFE AND METHOD OF USE Filed Dec. 1, 1954 v v 7 Sheets-Sheet 1 W 1s '3 W 42- 42:? m i 23 25 L 4:

INVEN T01? Joy/v. A. GAMME 72-7? ATTORNEY Yes oct. 13, 1936.

J. R. GAMMETER HOT KNIFE AND METHOD OF USE '7 Sheets-Sheet 2 Filed Dec. 1, 1934 lNVENTOR v Jim/v R. GAN/YfTfR I ATTORNEY Oct. 13, 1936. J, R GAMMETER 7 2,057,021

HOT KNIFE AND METHOD OF USE Filed Dec. 1, 1934 7Sheets-Sheet 5 INVENTO R JaH/v R. Gar/H5751;

1 I aw ATTORNEY Oct. 13, 1936. v J. R. GAMMETER 2,057,021

HOT KNIFE AND METHOD OF USE Filed Dec. 1, 1934 i 7 Sheets-Sheet 4 a w a INVENTOR .Tomv Kqnm-rema 0a. 13, 1936. R M TE 2,057,021

HOT KNIFE AND METHOD OF USE Filed Dec. 1, 1934 7 Sheets-Sheet 5 mvsuro J0H/v R. GAMMETEK WK g ATTORNEY Oct. 13, 1936. R GAMMETER 2,057,021

HOT KNIFE AND METHOD OF USE Filed Dec. 1, 1934 t '7 Sheets-Sheet 7 INVENTOR Jay/v R. GAMMETE W ATTORNEY Patented Oct. 13, 1936 U N I T ED STATE S O FFI C E 2,057,021 h HOT, KNIFE immense USE].

John R." Ginrnnete r;Akron, hio assignor to United States Rubber CompanyyNew'York; N. Y., a corporation-of NewfJersey l Application Decemherl, 1934-, sir,iai1rd. #755,598

15 Claims.

This invention relates to a method and apparatus for producing thread rubber from liquid latex or other rubber dispersions and hasfor its primary object a simplified method and improved thread rubber produced in an efiicient and inexpensive manner. I

A further object of the invention is to produce thread rubber in a continuous length from a sheet or band of rubber material applied-to .a resistible traveling belt or similar surface.

A further object of the invention resides .in separating the sheet or band of rubber material into a plurality of individual, continuous threads by the application of heat to the travelingsheet or band of rubber material. V v

A still further object of the invention is to provide means for maintaining the threadsfofathe severed sheet or band in predetermined relation and simultaneously to prevent the rubber threads from adhering to the separating means, i I

With the objects above indicated and other ob-, jects hereinafter explained in view, the invention consists in the construction, combinations of elements and method ashereinafter described and claimed.

Referring to the drawings,

Figure 1 is a side elevational view of. an ap aratus embodying the present invention, abortion thereof being in section to more clearly illus} trate the details of construction; r

Figure 2 is an end elevational view of the upper portion .of the apparatus made; upon an enlarged scale; 'f

Figure 3 is a vertical, sectional view. taken on line 3--3 of Figure 4;

Figure 4 is a top ,plan view of'the apparatus shown in Figure 1, but made upon an enlarged scale; I

Figure 5 is a fragmentary, sectional viewtake'n on line 55 of Figure 3 and made upon "an enlarged scale to more clearly illustrate the con: struction;

Figure 6 is a fragmentary, elevational, sectional view make upon an enlargedscale-to more clearly illustrate the construction; and

Figure 7 is a diagrammatic, elevational-view showing the means for maintaining the thread'of the severed sheet in predetermined relationif In the drawings, I 0 indicatesa pedestal preferably made of cast iron and having" a base H formed integral whereby the pedestal-maybe supported upon any desirable supporting-structure and secured in any suitable manner. 1 A horizontally disposed top member or plate I2 is formed integral with the upper end of the pedestal (cris z any, suitable distanceandspaced in parallelism J fora purposetobe later-described. I I

.A pair of cooperating mandrels l1 and 18 are positioned :transversely of the, 'baseplate, .l4 and upon opposite sides of avertically traveling metal belt;.l:9 upon whichthe rubber material 20 is deposited either. on one or both: sides-as may be desired asmore clearly shown in Figure 6.} The mandrel: l1 is of tubularhconstruction' and has a pair of spaced circumferential grooves 2! upon eachend thereof. Straps 22' have portions extendingabo-ut theends of the mandrel I'I between each'pairof grooves 2| and have laterally extending flanges 23 connected by bolts 23% to. a frame 24. Pairs of ball bearing rollers 25* are rotatably' mounted upon :opposite sides of the frame 24 and are disposed in the groovesZl on the side opposite to said straps, thereby rotatably supporting's'aid mandrel above and belowthe horizontal axes thereof as more clearly shown in Fig ure" 3. The frame 24 has an inwardly extending portion provided with an opening at its inner end'in which a bushing 21 is secured. A plate 28 is-secured to the upper surface of the baseplate' I l-by bolts 29 and has a screw-threaded'opening which receives the screw-threaded 'end of'a bolt30extending through the bushing 21 and about which the frame 24 is movable and may be securedin' proper position to align the mandrels l1 and [8. An arcuate' rib3l is formed upon the uppersidexofthe plate' 28 at the outerportion thereof and is' engaged by a similar depending rib 32 formed at the outer portionof'the frame 24- and by which the latter is supported. r v

Ametalbrush 33' is secured by nuts 34 to a transversely extending shaft 35,v the opposite ends of .whi'ch arejournald 1 in bearings 36. A

plate 3'l extendsacross the upper portion of the frame 24, and is secured at its. opposite ends to the frame by bolts. 38. int, ,manner to permit 5 transverseadjustment.= The bearings36 are secured to the under side of. the plate 31 by bolts 39 so 1 as to. be. movable therewith. The. adjust.- ability of the-plate31 affords means by which the ,brush- 3 ma ,-.be relatively positioned with respect to the mandrel I! for a purpose to be later described.

an endless belt 46 which provides a positive drive a for rotating the brush 33.

The mandrel l1 has spaced, exteriorly'screwthreaded portions 41 between which are arranged a plurality of circular knives 48 and intermediate spacers 49, the latter being of any desired thickness depending upon the gauge or size of thread rubber required. Sufficient clearance is provided between the knives and spacers and the outer surface of the mandrel to permit slight endwise movement for adjustment. Washers 5|] are positioned at the outer ends of the knives 48 and have pins 5| secured therein, the outer ends of which are disposed in slots 52 provided in the adjacent sides of the mandrel I! so as to prevent relative rotation but to permit endwise adjustment.

Screw-threaded nuts 53 cooperate with the screw-threaded portions 41 on the mandrel and engage the washers 56. Circumferentially spaced openings 54 are provided in the nuts 53 to receive a suitable wrench'by which they may be adjusted to clamp the knives and spacers in rigidrelation. This construction also permits replacing any of the knives in the event of injury or to substitute adiiferent size spacer to produce a different size thread. This construction is more clearly shown in Figure 5. a 7 7 Heat may be applied to the knives 48 in any suitable manner, but preferably by reason of the fact that the mandrel is hollow affords a ready application. In they present instance, a burner 55 extends longitudinally within the mandrel and one end projects therebeyond and is supported by a strap iron bracket 56 having its lower end connected to the base plate l4 by bolts 51 as clearly shown in Figure 2. A mixer and valve 58 is provided to control the flow of gas to the burner in anyjwell-known manner. The burner 55 has ports 59 whereby the gas may be ignited and the flames 60 play upon the inner periphery of the mandrel heating the same which in turn transmits the heat to the knives 48. The knives may be heated to any desired temperature for the purpose intended, but it has been found that a temperature from 200 to 300 F. is sufiicient and should be controlled by thermostatic means in any well-known manner.

While gas is here shown for the purpose of supplying heat to the knives, it should be understood, of course, that any other means may be employed such as steam, electricity, etc.

Due to the characteristics of the rubber material used there is a tendency for the cut threads to stick together and this may be prevented by dusting the sheet with talc either before or after the 'separatingjoperation or, as shown in the drawings, a felt roller 6| is secured to a rod 62 having its outer ends rotatably journaled ina bracket. 63 connected to the frame 24 by bolts 64. A receptacle 65 is secured to the bracket 63 and "positioned beneath the roller 6| as shown in Figure 3. The roller 6| contacts with the knives 48 on the mandrel l1 and is rotated byfrictional engagement therewith. A suitable coagulant is placed in the receptacle 65 and the roller 6| being partly submerged therein transfers the coagulant to the knives 48 just prior to their engagement with the rubber material upon the belt l9. As the knives separate the rubber material into threads the coagulant is applied to adjacent edges thereof which acts to prevent coherence between adjacent threads.

Inasmuch as the mandrel I8 is supported and operates in precisely the same manner as the mandrel heretofore described, it will not be necessary to further elaboratethereon except insofar asthe following differences are concerned.

The mandrel 8 is supported on a frame 66 similar to the frame 24, but in this instance the frame 66 is slidably mounted upon the upper side of a support, there being provided for this purpose cooperating slideway 68 at the opposite sides thereof. Plates 69 extend over the adjacent ends of the frame 66 and are secured by bolts 16 to the upper side of the support 6'! so as to i prevent accidental disengagement'but at the same time to permit free sliding movement of the frame 66. The support 61 is secured to the upper surface of the plate M by bolts 1| having T-shaped heads which are slidably disposed in the T-shaped grooves 16 to permit adjustment of the support 61. This construction permits the mandrel I8 to be moved toward the mandrel I! sothat the knives 48 will sever the rubber material deposited upon the belt I9 and to be moved into inoperative position with the knives 48 out of cooperative engagement.

The frame 66 may be moved manually or otherwise, but in the present instance a power actuated device operates to move the mandrel l8 into operative position but is moved to inoperative position by hand. At the outer side of the frame 66 is an extension 12 having an opening therethrough and is disposed in one of the bifurcated ends of a link 13 also provided with aligned openings to receive a bolt 14. The opposite bifurcated end of the link 13 also has aligned openings and receives the upper end of a lever 15 also provided with an opening to receive a bolt'l6. Intermediate the ends ofthe lever 15 is a bossed portion 11 having an opening therethrough and which is positioned between a pair of ears or extensions 18 formed integral with a bracket 19. The bracket 19 is secured to the adjacent side of the support 61 by bolts 80', the lever 15' being pivotally mounted upon a bolt 8| passing through aligned openings in the ears l8.

Thelower end of the lever 15 has a roller.82 pivotally mounted thereon which is adapted to. engage a head 83 on the outer end of a piston rod 84, the piston being mounted in a cylinder 85 in any well-known manner. The cylinder 85 is secured by bolts 86 to the pedestal I6 and the interior of the cylinder may be connected with any suitable source of compressed air or other fluid under pressure by means (not shown) whereby the piston is moved to exert an outward pressure on the end of the lever 15 in turn causing the mandrel I8 and knives to be moved into operating position. Any suitable means may be employed for controlling the supply to the cylinder. While a one-way power operation is illustrated, it should be understood that power may be employed to move lever 15 in both directions.

It has been found that a pressure of approximately 2 /2 to 3 pounds per knife is sufficient to sever. the rubber. material, but this, of course,

may be varied to suitthe conditions encountered. The means illustrated is well adapted to operate The metal belt I9 may beguidedupwardly intoproper position between the members IT and I8 by providing a sheave 81'rotatablyjournaled in bearings 88 secured to a bracket-89which in turn;

is bolted at 90 to the pedestal); upomhe opposite side from the cylinder 85. The metal" belt 19 may further be trained over similar "sheaves leading to and from a rubber material depositing station' at any desirable location as well 7 as through drying and vulcanizing stations in a manner well-known to those skilled in the art, all

in a continuous manner'and similar to that dethe sheet rubber material maybe separated into" threads upon opposite 'sides'of the belt l9 simultaneously, it should be understoodth'at the rub-j" ber material may be applied" to one side only and threads formed therefrom. In this latter instance only one set of knives are required adjacent the side of the beltupon which the rubber material has been applied and an ordinary'backing roll substituted for the other set of knives to'me'rely' afford resistance when the knives are moved into operating position.

It is, of course, essential that the mandrels l1 and I8 carrying the knives 48 rotate at the same speed as the travel of the belt l9 so that there is no tendency to sever or tear the sheets of material while being formed into threads. Of course it is much better that the knives 48 of both man: drels align transverselyas one then acts .as an abutment for the other during the thread-form-i ing operation as more clearlyshown in Figure 5. Also the threads may be formed square or with clean, sharp edges and of solidsection.

On the opposite ends'of themandrel l8, ex-. ternal gears 90 are mounted and are secured in place thereon by nuts 9l having screw-threaded engagement with the mandrel. The mandrel" l1 has, in. a similar manner, external gears,92'

mounted thereon and are secured in place by nuts 93 having screw-threaded engagementwith the mandrel. The gears 92 are positioned so as to mesh with the gears 90 on. the mandrel l'l'fso that both mandrels and their. knives wilLbe roe tated at .the same speed. 4

Either mandrel may, but as shown in the drawings the mandrel I1, have .anextension on one end upon which is secured a sprocket 94 which receives an endless chain 95, the latter being con-. nected in any suitable manner to the power source which drives the metal belt l9. This arrangement makes certain that the mandrels and their knives are positively rotated at-the'same peripheral speed and at the same longitudinal speed as the belt l9 during the thread-forming operation.

If it is desired to positively eliminate any tendency of the adjacent severed threads to stick to each other or to prevent the threads from stick-' ing between the knives or to insure that the threads adhere to the belt, one type of suitable apparatus is shown in Figure '7 which may be em-. ployed.

A pluralityof individual, .endless coils96 of wire of suitable gauge extendupwa'rdly in parallelism with the .beltl9.;and..ar.e; disposed between thegadj acent knives 48 on- -the mandrel H incontactwith the rubbermaterial as more clearly shown in Figure 5. The number of coils 96; of course, corresponds with the number of threads being" produced and-the coils may extend around atran'sverse-lygrooved sheave 91 above the machine-and'a similar transversely grooved sheave 98- rotatably mountedin bearings 99 bolted orotherwise secured to-pedestal [0 as shown in- Figure 1. These sheaves 9i and 98-are positioned in parallelism above and below the mandrels with thegrooves corresponding to the spacing between the knives 48. Similarly grooved sheaves IOU-may be=-suppotted "any suitable man-ner so as to support and "guide the coils in their travel in the direction -'of movement 'of the belt and by 'frictional contactwith the rubber material thereon.

Idler sheaves lUl also similarly grooved are'rotatably supported .between'the upper sheaves 91 and l D0 and the coils 96' are looped therebetween and extend around a grooved :roller' )2 to which an adjustable and detachable weight H13- is-connected to take up the slack in the coils and thereby maintain that portion'of the coils which con-' tact with the rubber material and thread in parallelism. 7

An identicalarrangement for the endless coils Hi4: associated with the mandrel l8 isprovided and therefore needs no further explanation.

-Briefiy the operation is as follows With'the mandrel l8-slightly spaced from themandrel I! in inoperative position, the mandrel ILif found to be out of parallelism with the belt l9, may be adjusted in the manner described and secured in adjusted position. The main drive for the belt I9 is'then started with the result that the mandrels Hand l 8 are positively rotated at the same speed as the travel of the belt.:- The burners55, having been lighted, heat the mandrels and knivescarried' thereby to the proper temperature and this temperature is automatically-maintained.

Thai-rubber material applied to the belt I9 is then being moved toward the knives 48 and the mandrel I8 is then moved toward the mandrel I! to bring the knives 4B into-contact with the rubber material on the belt. The heated knives sen-- arate-therubber material into threads during the upward travel of the belt and the piston in the cylinder is moved'outwardly by the admitted airto 'move'the frame 61 carrying the mandrel l8and knives into contact with the rubber materialand to I maintain the required pressure thereon; Inasmuch as the mandrels and belt rotate and travel respectively at the same surface speed continuously, the rubber'material is separated into threadscontinuously and without any shearing action. During the rotationof the mandrels coagulant is applied to the knives by means of the rollers 6| just prior to their'engagement with the rubber material which results in coagulating the edges of adjacent threads to prevent sticking. The: brushes 33 may be rotated by means of the motors 42 and by their contact with the knives the latter are continuously cleaned. After the threads have been produced they may remain on the belt and be cured or they may be stripped therefrom and subsequently cured. I

If. it is found that the threads tend to stick between adjacent knives or pullloose from the belt, the coiled wire apparatus maybe used in the manner heretofore described.

While the apparatus is-designed especially for dipping and applyinglatexor rubber dispersions to -the; belt .I 9;. it. should also .be understood that any suitable ,rubber material may be spread'or otherwiseapplied to the belt on one or both sidesthereof. Q p e While I have described the preferred embodiment of the invention,;. it should be understood that I am not to be limitedtheretoinasmuchas changes and modifications may be resorted to without departing from the spirit of the invention asdefined in'the appended claims,

What is. claimed is:

- 1. In an apparatus for forming rubber threads and the like, a continuously moving belt for conveying rubber material in sheet form, a backing means on one side ofv said belt and engageable therewith, a plurality of spaced knives rotatably mounted on the other side of said belt and adapted to engage the rubber-material, means for heating said knives to a temperature sufiicient to sever the rubber material, and compressed air means for yieldingly moving said knives into and out of engagement withv the rubber material and for maintaining a predetermined pressure thereon.

2. In an apparatus for forming rubber threads and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, relatively movable cooperating severing means between which said belt passes and adapted to engage the rubber material on adjacent sides of said belt, means for heating said severing means to a temperature sufficient to sever the rubber material, and means for relatively moving said severing means into and out of engagement with the rubber material on said belt.

3. In an apparatus for forming rubber threads and. the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, relatively movable cooperating knives rotatably mounted on opposite sides of said belt and adapted to engage the rubber material on the adjacent side of said belt, means for rotating said knives at the same peripheral speed as the lineal speed of said belt, means for heating said knives to a temperature suflicient to sever the rubber material, and means for relatively moving said knives into and out of engagement with the rubber material on said belt.

4. In an apparatus for formingrubber threads and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, relatively movable cooperatingknives rotatably mounted on opposite sides of said belt and adapted to engage the rubber material on the adjacent side of said belt, means for rotating said knives at the same peripheral speed as the lineal speed of said belt, means for heating said knives .to a temperature suflicient to sever the rubber material, and means for moving said knives relatively to engage the rubber material on said belt and to maintain a predetermined pressure thereon.

5. In an apparatus for forming rubber threads and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, a set of axially spaced knives rotatably mounted on one side of said belt and adapted to engage the rubber material on the adjacent side of said belt, a second set of axially spaced knives'rotatably mounted on the opposite side of'said belt and adapted to engage the rubber material on the adjacent-side of said. belt, means for rotating said sets ofzknives, and means for heating said sets of knives'to a temperature suflicient to sever the rubber material.

6. In an apparatus'forforming rubberthreads and the-like, a continuously traveling belt adapted to convey rubber material on both sidesthereof in sheet form, a set of axially spaced knives rotatably mountedon one side of said belt and 7 adapted to engage the rubber material on the adjacent side of saidbelt, a second set of axially spaced knives rotatably mounted on the opposite side of saidbelt and adapted to'engage the rubber. material on the adjacent side of said belt, one of said setsof knives being adjustable transversely of its axis of rotation and the other set of knives being movable toward and'away from said first set of knives, means for rotating said sets oi knives, means for heating said sets of knives to a temperature suflicient to sever the rubber material, and means for moving said move able set of knives into and out of engagement with the rubber material on the adjacent side of said belt. r

.7. In an apparatus for forming rubber threads and the like,,a continuously traveling belt adaptedto convey rubber material on both sides thereof in sheet form," a set of axially spaced knives and the like, a continuously traveling belt adapt-7 ed to convey rubber material on both sides thereof insheet form, a set ofaxially spaced knives rotatably mounted on one side'of said belt and adapted to-engage the rubber material on the:

adjacent side of saidv belt, a second set of axially spaced knives rotatably mounted on the opposite side of said belt and adapted to engage the rubber'material on the adjacent sideof said belt, means for rotating said sets of knives in unison and at the same peripheral speed as the lineal speed of said belt, means for heating said sets of knives to a" temperature sufficient to sever the rubber material, and means for moving one set of knives into and out of engagement with the rubber mat'erialon the adjacent side of said belt.

9. In an apparatus for forming rubber threads and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, a pair of hollow mandrels rotatably mounted on opposite sides of said belt, a plurality of axially spaced knives secured to each of said mandrelsand adapted to engage the rubber material on the adjacent sides of said belt, heating means disposed Within said mandrels and adapted to heat said knives to a temperature sufiicient to sever the rubber material, and means for rotating said mandrels in unison and at the same peripheral speed as the lineal speed of said belt.

10. In an apparatus for forming rubber threads and the like, a continuously traveling belt adapted. to convey rubber material on both sides thereof in sheet form, a pair of hollow mandrels rotatably mounted on opposite sides of said belt, a plurality of axially spaced knives secured to each of said mandrels and adapted to engage the rubber material on the adjacent sides of said belt, heating means disposed within said mandrels and adapted to heat said knives to a temperature sufficient to sever the rubber material, means for rotating said mandrels in unison and at the same peripheral speed as the lineal speed of said belt, and means for moving one of said mandrels to- Ward and away from said belt.

11. In an apparatus for forming rubber threads and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, a pair of hollow mandrels rotatably mounted on opposite sides of said belt, a plurality of axially spaced knives secured to each of said mandrels and adapted to engage the rubber material on the adjacent sides of said belt, heating means disposed within said mandrels and adapted to heat said knives to a temperature sufiicient to sever the rubber material, automatic means for controlling said heating means, and means for rotating said mandrels in unison and at the same peripheral speed as the lineal speed of said belt,

12. In an apparatus for forming rubber threads and the like, a, continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, a pair of hollow mandrels rotatably mounted on opposite sides of said belt, a plurality of axially spaced knives secured to each of said mandrels and adapted to engage the rubber material on the adjacent sides of said belt, heating means disposed within said mandrels and adapted to heat said knives to a temperature suflicient to sever the rubber material, means for rotating said mandrels in unison and at the same peripheral speed as the lineal speed of said belt, and means for urging one of said mandrels toward the other to provide a predetermined pressure between said knives and the rubber material on said belt.

13. That method of forming rubber threads or -and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, narrow disc-like severing knives rotatably mounted on opposite sides of said belt and adapted to engage the rubber material on the adjacent sides of said belt and to pass through the rubber material into backing engagement with said belt whereby the knives on one side of the belt act as backing means for the belt with respect to the other set of knives, and means for heating said knives to a temperature sufficient to sever the rubber material.

15. In an apparatus for forming rubber threads and the like, a continuously traveling belt adapted to convey rubber material on both sides thereof in sheet form, rotatable severing elements between which said belt passes and adapted to engage the. rubber material on adjacent sides of said belt whereby said severing elements on one side of the belt act as backing means for the belt with respect to the severing elements on the other side thereof, and means for rotating said severing elements and advancing the belt with a rubber sheet upon each of its faces therebetween.

JOHN R. GAMMETER. 

